The present application relates to communication networks, and particularly to communication networks which use existing physical channels of communication which cooperatively form a new system for transfer of information in at least one, and preferably two, directions without the construction of additional physical communication channels or major upgrades to existing physical communication channels. The structure disclosed in this application has application for the automatic reading of various meters provided in homes, businesses, and institutions, as well as in electronic mail, electronic TELEX.TM.-type applications and security systems, and other data communication applications, as but some examples.
Various systems have been proposed for establishing a communication network between individual subscribers and certain utilities, such as the water utility, the gas utility, or the electric utility, whereby the meter of the particular utility is read electronically and the reading forwarded to the utility electronically. To a large extent, many of these systems required a telephone communication link being initiated by the utility causing the telephone within the subscribers' dwelling to be activated. Some arrangements placed equiptment before the telephone to recognize an incoming signal, however, these have not proven popular. The main problem with this system is that all phones are activated by the incoming call resulting in inconvenience to the subscriber.
It has also been proposed to utilize existing cable television systems as a two way communication channel; however, owing to the high cost of conversion from one-way to two-way, such systems have proven to date only to be speculative. It has also been recognized that it would be possible to again hard wire a further communication channel within a city or region which is in effect what has happened with the use of TELEX systems; however, the cost for doing this has been prohibitive in most cases.
According to the present invention, a new utility or central processor or intermediary is proposed which would function much as the existing utilities for supplying the telephone services. This service would be particularly useful for the electrical utilities, water utilities, gas utilities as prime examples, and could also be used for electronic mail used by corporations and individuals. Basically, a new communication utility can be established which uses existing communication channels without modification, thus avoiding the massive investment in additional equipment for existing communication systems or for new communication systems that has been proposed in prior art arrangements. In effect, according to the present application, this communication utility is possible and will work in a way very similar to a new wire based communication network without requiring the massive investment for such a new communication network.
According to the present invention, the communication system combines the communication capabilities of the telephone and broadcast media with the power of distributed micro-processor intelligence. This system requires a receiver installed on the premises of each subscriber which interfaces with various communication channels including the telephone communication channel and, in certain cases, a cable television outlet. The receiver is adapted to continually "hear" a broadcast signal either sent on the free air or over the cable TV network. In this way, the receiver is always "listening" for its identification signal and, upon matching its identification signal with a received signal, it initiates a telephone communication from the receiver to the central processing facility. In this way, the problems associated with a telephone call being placed to the subscriber from the processing facility are avoided.